Том 43, № 6 (2016)

The phylogenetic relationships and taxonomic position of sea stars of the family Porcellanasteridae have been a subject of debate for over a hundred years. In this paper, the methods of molecular phylogenetic analysis were used to solve these issues. The nucleotide sequences of fragments of the mitochondrial gene of subunit 1 of cytochrome oxidase (COI) and those of the 16S rRNA gene were obtained for 9 and 6 species of porcellanasterids for the first time, respectively. The phylogenetic trees including these sequences indicate the nearest relationships of the family Porcellanasteridae with the families Ctenodiscidae and Goniopectinidae, thereby supporting the validity of the allocation of these three families in the suborder Cribellina.

In comparison with Asteroidea, the axial complex of ophiuroids has some important features, which are the result of shifting of the madreporite from the aboral side to the oral side. In contrast to Asteroidea, the stone canal of ophiuroids connects with the water ring from the outside, not from the inside. In Ophiuroidea, the somatocoelomic perihaemal coelom is closer to the mouth than the axocoelomic ring. The water ring of ophiuroids is shifted to the oral side relative to the perihaemal coelomic rings. The genital coelom and gastric haemal ring are located on the outer side of the axial complex, whereas in Asteroidea, they are located on the inner side. The pericardial part of the axial organ is situated on the oral side. The interradial sections of the genital coelom and genital haemal ring are descended to the oral side. Our hypothesis considers that the ancestors of ophiuroids turned the aboral side of the animal to the substratum. It caused shifting of the madreporite to the oral side and closing of the anus.

Nuclear magnetic resonance spectroscopy revealed the presence of lactic acid and alanine in the coelomic fluid of the black sea urchin Mesocentrotus nudus, which indicates the presence of anaerobic metabolism in echinoderms. It was found that this way of energy metabolism is intensified in stressful situations with insufficient intake of oxygen by the cells and that this compensatory response of energy metabolism is an important adaptive mechanism to changes in environmental conditions.

The results of chemotaxonomic research on triterpene glycosides of holothurians (Holothurioidea, Echinodermata) and studies on the ecological role of these glycosides as protective substances and trophic markers are reviewed with a focus on research performed in 2011–2015.

By using morphometric and molecular-genetic methods, the population of honeybees of apiaries located in the mountain-forest zone of the Crimean Peninsula under conditions of prolonged isolation from other bee farms of the peninsula was studied. The hypothesis that the bees of this apiary may show signs of lost Crimean bees was analyzed. The complex of morphological traits makes the bees of the examined apiaries closer to Italian, Krajina, and Ukrainian steppe bees and, to a lesser extent, to Carpathian bees. The results of molecular genetic analysis of the initial part of the mtDNA COI gene from GenBank for the races under consideration revealed the evolutionary proximity of the bees studied to representatives of Italian bees. The bees of the isolated apiary are united into a single haplotype. The sequences of the mtDNA COI locus were obtained from Carpathian bees from Moscow oblast and Tajikistan. In terms of differences between the Italian bee haplotype and haplotypes of bees from other regions related to Carpathian bees, it is suggested that the haplotypes of the apiary studied are more similar to Carpathian bees. The investigations do not reject the hypothesis that bees of the isolated apiary may have traits typical of Crimean bees.

The toxic effects of synthetic nitriles and nitrile herbicides on some bacterial species were estimated. Biotests based on bioluminescence revealed that aromatic nitriles including herbicides had the most significant toxic effect on bacteria, which differed from their effect on eukaryotic cells. It was shown that soil strains of nitrile-utilizing bacteria were resistant to high concentrations of the studied compounds. The minimal bactericidal concentrations for most of nitriles were 0.5 M or above. It was demonstrated that exposure to 0.1 and 1 mM bromoxynil solution resulted in a decrease in the linear parameters of the cells of all strains and sufficient changes in the cell surface of Gram-negative bacteria. It was proposed that the toxic effect of aromatic herbicides was caused not only by inactivation of an enzyme of the electron-transport chain but also by damage to the surface structures.

The surface of nutlets and the ultrasculpture of еру pericarp were studied for the first time using a scanning electron microscopy in nine species of the genus Mentha, growing in Russia and neighboring countries. Three types of primary and four types of secondary seed surface sculptures were identified. It was found that the ultrasculptural features of the nutlet pericarp can be used in the taxonomy of the genus at the level of species and for identifying the relationship between taxa.

The role of the male acoustic signal in courtship behavior in Drosophila virilis was studied by a video-typing method. Three series of the experiments were performed: tests with intact flies, with wingless males and intact females, and with intact males and females with the aristas removed. It was demonstrated that touching and licking were the most prolonged elements of the male courtship. It was noted that removal of the wings in males or aristas in females resulted in an increase in the duration of almost all elements of the courtship behavior (following, touching, licking, singing, and circling) and in a significant decrease in the portion of successful copulations. It was demonstrated that the courtship structure in the experiments with females without aristas changed to a greater extent than in tests with wingless males.

A comparative analysis of the intestinal microbiomes of some representatives of the Lake Baikal endemic family Comephoridae—the big oilfish Comephorus baicalensis (Pallas, 1776) and the little oilfish C. dybowski (Korotneff, 1904)—has been performed for the first time. The phylotype Akkermansia (phylum Verrucomicrobia) was detected in the C. dybowski microbiome, while Alistipes, Bacteroides, Chryseobacterium, Prevotella (Bacteroidetes), and Peptoniphilus (Firmicutes), were found in the C. baicalensis microbiome. Their presence in the intestine is associated with an elevated lipid uptake or an increase in the human and animal body weight. It is hypothesized that these microorganisms are involved in the lipid metabolism of the oilfish and determine their morphophysiological adaptations to pelagic life.